Re: Attaching HDPE

["Randy" <randy-at-gte-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Subject: Re: Attaching HDPE


> Original poster: "David Trimmell" <davidt-at-pond-dot-net>
>
> Yes, short of some really expensive solvents (can't remember names, but do
> know they are not within reasonable cost, even for independently wealthy
> coilers), PE can only be welded or cast (molded, I suppose). I  guess a
> proper hot melt glue formulation (higher melt point resin/wax formulation)
> with a sufficiently hot "gun" could work for "welding" PE to PE, but
forget
> anything else. Nylon screws sounds best.
>
> Regards,
>
> David Trimmell
> www.ChaoticUniverse-dot-com
>

A division of the company I work for specializes in sewer rehab by towing
successive lengths (41 ft.) of HDPE, bonded together by squaring off the
ends, heating the ends, and pressing the two pieces together with the same
jig used to square the pieces, resulting in about a quarter-inch bead of the
PE both inside and outside the pipe. The pipes are then towed thru the
existing
line by a cable attached to a metal cone with a single blade protruding. I
don't
know what the limit of line length, but it's apparently a function of the
cable
length. They have been at it for a few months now, and have had *no*
failures of the weld-joint. They can actually pull an *8* inch pipe thru a
existing *6* in line.....one can imagine what the frictional load must
be....

FWIW the lines we use are black, but I've also seen yelllow around alot
lately; I believe it's used for natural gas, but could be wrong.

Also, I should add that the 41 ft. sticks are all welded together prior to
commencing the "pull", resulting in an unwieldy mass that must weave
around whatever obstructions populate the jobsite, so I have to believe
that there are some serious side-loads exerted in addition to the friction
of the towed pieces.

I'm sorry I don't have time to read all the posts anymore, but if anyone
needs any more info, please feel free to email me directly at randy-at-gte-dot-net

Best Regards,

Randy

> At 07:02 PM 8/7/00 , you wrote:
> >Original poster: "Gomez ADDams" <gomez-at-netherworld-dot-com>
> >
> >on that fateful day 8/7/00 5:00 PM, Tesla list uttered:
> >
> >> Original poster: Terry Fritz <twftesla-at-uswest-dot-net>
> >>
> >> Hi Ted,
> >>
> >> Hot melt glue and nylon screws.  Not much else even "tries" to stick to
> >> poly...
> >
> >What brand/type of hot melt are you using that sticks to polyethylene?
I've
> >never been able to get _anything_ to stick to it, not even hot melt
> >adhesives.  After all, polyethylene is only a few fluorine atoms away
from
> >being Teflon.  ;)
> >
> >- Gomez
> >
> >..............................................................
> >"The most fundamental human right is ownership of your body.
> >If you cannot do with it as you please, you are not yet free."
> >                                 - W. A. Lemieux
> >
> >
> >
>
>
>